CN112823031B

CN112823031B - Fluid injector systems, methods, and computer program products for preventing backflow of fluids

Info

Publication number: CN112823031B
Application number: CN201980056142.0A
Authority: CN
Inventors: M.麦克德莫特; W.巴隆; J.沃尔卡
Original assignee: Bayer Healthcare LLC
Current assignee: Bayer Healthcare LLC
Priority date: 2018-08-28
Filing date: 2019-08-27
Publication date: 2023-08-15
Anticipated expiration: 2039-08-27
Also published as: CA3110859A1; JP7450608B2; EP3843808A1; WO2020046869A1; US20210220556A1; CN112823031A; JP2021534900A; AU2019329731A1

Abstract

A fluid injector system includes a control device operatively associated with each of two or more drive members configured to pressurize and inject a first fluid from a first fluid reservoir through a fluid conduit and to pressurize and inject at least a second fluid from a second fluid reservoir through a fluid conduit. The fluid conduit is in selective fluid communication with the first and second fluid reservoirs. The control device has at least one processor programmed or configured to actuate the second drive member to pressurize and inject the second fluid through the fluid conduit, and upon actuation of the second drive member, actuate the first drive member to introduce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

Description

Fluid injector systems, methods, and computer program products for preventing backflow of fluids

Cross Reference to Related Applications

The present application claims priority from U.S. provisional patent application No.62/723,739 filed on 8.28 of 2018, the disclosure of which is incorporated herein by reference in its entirety.

Technical Field

The present disclosure relates to fluid injector systems, and in particular, to fluid injector systems configured to perform an injection protocol. The present disclosure also relates to methods of preventing backflow of a second fluid from a second fluid reservoir into a first fluid reservoir during a fluid injection process using a fluid injector system. The present disclosure also relates to a computer program product for preventing backflow of at least a second fluid from a second fluid reservoir into a first fluid reservoir during a fluid injection process using a fluid injector system.

Background

In many medical diagnostic and therapeutic procedures, a medical practitioner (such as a physician or radiologist) injects one or more fluids into a patient. In recent years, several injector-actuated syringes and powered injectors for pressurized injection of fluids have been developed for use in procedures such as angiography, computed Tomography (CT), molecular imaging (such as PET imaging), and Magnetic Resonance Imaging (MRI). In these procedures, a fluid, such as a contrast agent, may be used to emphasize certain internal organs or body parts during the imaging procedure. At the same time, saline or similar flushing agents may be used to ensure complete injection of the contrast agent bolus or to adjust the concentration of the contrast agent.

For fluid injector systems with multi-reservoir disposables (multi-reservoir disposables) that are configured to deliver more than one fluid type, it is desirable to prevent inadvertent mixing of two fluids in different reservoirs. This may be particularly relevant for multi-patient applications, where the same reservoir(s) may be used to deliver fluids to multiple patients over the lifetime of a disposable reservoir. Unintentional mixing of contrast agent into the saline reservoir may lead to errors in patient dose during the test injection or flushing phases. Conversely, inadvertent mixing of saline into the contrast reservoir may result in undesirable amounts of diluent, producing non-diagnostic or degraded quality images. Accordingly, there is room for improvement in fluid injector systems, methods, and computer program products for use therein that prevent backflow of fluids.

Disclosure of Invention

Embodiments of the disclosed examples or aspects address these needs and others, which are related to improved fluid injector systems, methods of preventing backflow of fluids, and computer program products for use therein.

In some examples or aspects of the present disclosure, a fluid injector system configured to perform an injection protocol is provided. The fluid injector system includes a control device operatively associated with each of the two or more drive members configured to pressurize and inject a first fluid from a first fluid reservoir through a fluid conduit, and to pressurize and inject at least a second fluid from a second fluid reservoir, the fluid conduit being in selective fluid communication with the first fluid reservoir and the at least second fluid reservoir. The control device has at least one processor programmed or configured to actuate a second of the two or more drive components to pressurize and inject a second fluid through the fluid conduit, and upon actuation of the second drive component, actuate a first of the two or more drive components to induce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

In some examples or aspects of the present disclosure, another fluid injector system configured to perform an injection protocol is provided. The fluid injector system includes a control device operatively associated with each of the two or more drive members configured to pressurize and inject a first fluid from a first fluid reservoir through a fluid conduit, and to pressurize and inject at least a second fluid from a second fluid reservoir, the fluid conduit being in selective fluid communication with the first fluid reservoir and the at least second fluid reservoir. The control device has at least one processor programmed or configured to actuate a second of the two or more drive components to pressurize and inject a second fluid through the fluid conduit, upon actuation of the second drive component, actuate the first of the two or more drive components to induce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit to prevent backflow of the second fluid through the fluid conduit into the first fluid reservoir, continue to induce intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid, decrease intermittent pulses of the first fluid, and deliver the first fluid through the fluid conduit at a first fluid flow rate and deliver the second fluid at a second fluid flow rate at a desired ratio of the first fluid and the second fluid, monitor the pressure in the first fluid reservoir and the pressure in the second fluid during injection of the first fluid to determine whether a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches the first conduit or a predetermined value is initiated by the first fluid, and the second fluid is prevented from being injected into the first conduit, the intermittent pulses of the first fluid is prevented from reaching a predetermined value.

In some examples or aspects of the present disclosure, methods of preventing backflow of a second fluid from a second fluid reservoir into a first fluid reservoir in a fluid injector system configured to perform an injection protocol are provided. The method includes providing a control device operably associated with a first drive component configured to pressurize and inject a first fluid through a patient fluid line and a second drive component configured to pressurize and inject at least a second fluid from a second fluid reservoir through the fluid line; actuating a second drive member of the two or more drive members to pressurize and inject a second fluid through the fluid conduit; and upon actuation of the second drive member, actuating a first drive member of the two or more drive members to introduce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

In some examples or aspects of the present disclosure, a computer program product is provided for preventing backflow of at least a second fluid from a second fluid reservoir into a first fluid reservoir using a fluid injector system configured to perform an injection protocol. The fluid injector system includes a control device operatively associated with each of the first drive member and the second drive member, the first drive member configured to pressurize and inject a first fluid through the fluid conduit, and at least the second drive member configured to pressurize and inject a second fluid through the fluid conduit, the fluid conduit in selective fluid communication with the first fluid reservoir and the second fluid reservoir. The computer program product has a non-transitory computer readable medium containing one or more instructions that, when executed by at least one processor, cause the at least one processor to actuate the second drive component to pressurize and inject the second fluid through the fluid conduit, and upon actuation of the second drive component, actuate the first drive component to introduce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

Various other aspects of the disclosure are recited in one or more of the following clauses:

clause 1, a fluid injector system configured to perform an injection protocol, the fluid injector system comprising: a control device operatively associated with each of two or more drive components configured to pressurize and inject a first fluid from a first fluid reservoir through a fluid conduit and at least a second fluid from a second fluid reservoir through the fluid conduit, the fluid conduit being in selective fluid communication with the first fluid reservoir and at least the second fluid reservoir, the control device comprising at least one processor programmed or configured to: actuating a second drive member of the two or more drive members to pressurize and inject the second fluid through the fluid conduit; and upon actuation of the second drive member, actuating a first drive member of the two or more drive members to introduce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

Clause 2 the fluid injector system of clause 1, wherein the at least one processor is further programmed or configured to actuate a first drive component of the two or more drive components to continue introducing intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 3, the fluid injector system of clause 1 or 2, wherein the at least one processor is further programmed or configured to further actuate a first drive component of the two or more drive components to introduce intermittent pulses of the first fluid at a frequency or amplitude selected from the group consisting of increased frequency, decreased frequency, increased amplitude, decreased amplitude, and any combination thereof based on a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, an observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, a detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof.

Clause 4 the fluid injector system of any of clauses 1-3, wherein the at least one processor is further programmed or configured to reduce at least one of a frequency and an amplitude of intermittent pulses of the first fluid or to change a waveform of the intermittent pulses of the first fluid, and to deliver the first fluid at a first fluid flow rate and the second fluid at a second fluid flow rate through the fluid conduit at a desired ratio of the first fluid and the second fluid.

Clause 5 the fluid injector system of any of clauses 1-4, wherein the at least one processor is further programmed or configured to monitor at least one of the pressure in the first fluid reservoir and the pressure in the second fluid reservoir during injection of the first fluid and the second fluid to determine if a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches a first predetermined value.

Clause 6 the fluid injector system of clause 5, wherein, upon reaching the first predetermined value, the at least one processor is further programmed or configured to initiate a second set of intermittent pulses of the first fluid through the fluid conduit to prevent the second fluid from entering the first fluid reservoir.

Clause 7 the fluid injector system of any of clauses 1-4, wherein the at least one processor is further programmed or configured to monitor an injection pressure in the fluid conduit and determine if the injection pressure has changed by a second predetermined value.

Clause 8 the fluid injector system of any of clauses 1-4, wherein the at least one processor is further programmed or configured to calculate a predetermined injection pressure based on at least one of a programmed injection scheme and user input information, and in response, adjust a preset waveform of the intermittent pulses.

Clause 9 the fluid injector system of any of clauses 1-8, wherein the at least one processor is further programmed or configured to continuously monitor a rate of change of injection pressure in the fluid conduit, and in response, adjust at least one of a pulse interval, a pulse flow rate, and a pulse amount of the intermittent pulses based on a look-up table or a predetermined algorithm.

Clause 10 the fluid injector system of any of clauses 1-9, wherein when introducing intermittent pulses of the first fluid, the at least one processor is further programmed or configured to select a pulse interval from a look-up table or a predetermined algorithm.

Clause 11 the fluid injector system of clause 10, wherein when introducing intermittent pulses of the first fluid, the at least one processor is further programmed or configured to select a pulse flow rate from a look-up table or a predetermined algorithm.

Clause 12 the fluid injector system of any of clauses 1-11, wherein the at least one processor is further programmed or configured to select a pulse amount from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

Clause 13 the fluid injector system of any of clauses 10 to 12, wherein at least one of the look-up table and the predetermined algorithm is stored in a memory device.

The fluid injector system of any of clauses 1-13, wherein less than 40 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 15 the fluid injector system of clause 14, wherein less than 25 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 16 the fluid injector system of any of clauses 1-15, wherein, when the first drive component introduces intermittent pulses of the first fluid to create the flow front interface between the first fluid and the second fluid in the fluid conduit, a total volume of the first fluid introduced into the fluid conduit is less than a sum of a user-programmed volume and 15 milliliters.

Clause 17 the fluid injector system of any of clauses 1-16, wherein upon actuation of the first drive component, the volumetric volume of the first fluid reservoir increases and no second fluid enters the first fluid reservoir.

Clause 18, a fluid injector system configured to perform an injection protocol, the fluid injector system comprising: a control device operatively associated with each of two or more drive components, the two or more drive components configured to pressurize and inject a first fluid from a first fluid reservoir through a fluid conduit and at least a second fluid from a second fluid reservoir through the fluid conduit, the fluid conduit in selective fluid communication with the first fluid reservoir and at least the second fluid reservoir, the control device comprising at least one processor programmed or configured to: actuating a second drive member of the two or more drive members to pressurize and inject the second fluid through the fluid conduit; upon actuation of the second drive member, actuating a first drive member of the two or more drive members to introduce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir; continuing to introduce intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid; reducing at least one of a frequency and an amplitude of intermittent pulses of the first fluid or changing a waveform of intermittent pulses of the first fluid and delivering the first fluid at a first fluid flow rate and delivering the second fluid at a second fluid flow rate through the fluid conduit at a desired ratio of the first fluid and the second fluid; monitoring at least one of the pressure in the first fluid reservoir and the pressure in the second fluid reservoir during injection of the first fluid and the second fluid to determine if a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches a first predetermined value, or monitoring the injection pressure in the fluid conduit and determining if the injection pressure changes by a second predetermined value; and upon reaching a corresponding one of the first predetermined value and the second predetermined value, initiating a second set of intermittent pulses of the first fluid through the fluid conduit to prevent the second fluid from entering the first fluid reservoir.

Clause 19, the fluid injector system of clause 18, wherein the at least one processor is further programmed or configured to further actuate a first drive component of the two or more drive components to introduce intermittent pulses of the first fluid based on at least one of a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, an observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, a detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof, at a frequency or amplitude selected from the group consisting of an increased frequency, a decreased frequency, an increased amplitude, a decreased amplitude, and any combination thereof.

Clause 20 the fluid injector system of clauses 18 or 19, wherein the at least one processor is further programmed or configured to calculate a predetermined injection pressure based on at least one of the programmed injection scheme and the user input information, and in response, adjust the preset waveform of the intermittent pulses.

Clause 21 the fluid injector system of any of clauses 18 to 20, wherein the at least one processor is further programmed or configured to continuously monitor a rate of change of injection pressure in the fluid conduit, and in response, adjust at least one of a pulse interval, a pulse flow rate, and a pulse amount of the intermittent pulses based on a look-up table or a predetermined algorithm.

Clause 22 the fluid injector system of any of clauses 18 to 21, wherein when intermittent pulses of the first fluid are introduced, the at least one processor is further programmed or configured to select a pulse interval from a look-up table or a predetermined algorithm.

Clause 23 the fluid injector system of clause 22, wherein when introducing intermittent pulses of the first fluid, the at least one processor is further programmed or configured to select a pulse flow rate from a look-up table or a predetermined algorithm.

Clause 24 the fluid injector system of any of clauses 18 to 23, wherein when intermittent pulses of the first fluid are introduced, the at least one processor is further programmed or configured to select a pulse amount from a look-up table or a predetermined algorithm.

Clause 25 the fluid injector system of any of clauses 22-24, wherein at least one of the look-up table and the predetermined algorithm is stored in a memory device.

The fluid injector system of any of clauses 18-25, wherein less than 40 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 27 the fluid injector system of clause 26, wherein less than 25 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 28 the fluid injector system of any of clauses 18-27, wherein, when the first drive component introduces intermittent pulses of the first fluid to create the flow front interface between the first fluid and the second fluid in the fluid conduit, a total volume of the first fluid introduced into the fluid conduit is less than a sum of a user-programmed volume and 15 milliliters.

The fluid injector system of any of clauses 18-28, wherein upon actuation of the first drive component, the volumetric capacity of the first fluid reservoir increases and no second fluid enters the first fluid reservoir.

In a fluid injector system configured to perform an injection protocol, a method of preventing backflow of a second fluid from a second fluid reservoir into a first fluid reservoir, the method comprising: providing a control device operably associated with a first drive component configured to pressurize and inject the first fluid through a patient fluid conduit and a second drive component configured to pressurize and inject at least a second fluid from the second fluid reservoir through the fluid conduit; actuating a second drive member of the two or more drive members to pressurize and inject the second fluid through the fluid conduit; and upon actuation of the second drive member, actuating a first drive member of the two or more drive members to introduce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

Clause 31 the method of clause 30, further comprising programming or configuring the at least one processor to actuate a first drive component of the two or more drive components to continue introducing intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

The method of clause 32, further comprising programming or configuring the at least one processor to further actuate a first drive component of the two or more drive components to introduce intermittent pulses of the first fluid at a frequency or amplitude selected from the group consisting of increased frequency, decreased frequency, increased amplitude, decreased amplitude, and any combination thereof based on a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, an observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, a detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof.

Clause 33 the method of any of clauses 30 to 32, further comprising programming or configuring the at least one processor to reduce at least one of the frequency and the amplitude of the intermittent pulses of the first fluid or to change the waveform of the intermittent pulses of the first fluid, and to deliver the first fluid at a first fluid flow rate and the second fluid at a second fluid flow rate through the fluid conduit at a desired ratio of the first fluid and the second fluid.

The method of any of clauses 30 to 33, further comprising programming or configuring the at least one processor to monitor at least one of the pressure in the first fluid reservoir and the pressure in the second fluid reservoir during injection of the first fluid and the second fluid to determine if a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches a first predetermined value.

Clause 35 the method of clause 34, further comprising, upon reaching the first predetermined value, initiating, with the at least one processor, a second set of intermittent pulses of the first fluid through the fluid conduit to prevent the second fluid from entering the first fluid reservoir.

The method of any of clauses 30 to 33, further comprising programming or configuring the at least one processor to monitor an injection pressure in the fluid conduit and determine if the injection pressure has changed by a second predetermined value.

Clause 37 the method of any of clauses 30 to 33, further comprising programming or configuring the at least one processor to calculate a predetermined injection pressure based on at least one of a programmed injection scheme and user input information, and in response, adjusting a preset waveform of the intermittent pulses.

Clause 38 the method of any of clauses 30 to 37, further comprising programming or configuring the at least one processor to continuously monitor the rate of change of the injection pressure in the fluid conduit, and in response, adjust at least one of the pulse interval, pulse flow rate, and pulse amount of the intermittent pulses based on a look-up table or a predetermined algorithm.

Clause 39 the method of any of clauses 30 to 38, further comprising selecting, with the at least one processor, a pulse interval from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

Clause 40 the method of clause 39, further comprising selecting, with the at least one processor, a pulse flow rate from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

Clause 41 the method of any of clauses 30 to 40, further comprising selecting, with the at least one processor, a pulse amount from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

Clause 42 the method of any of clauses 39 to 41, wherein at least one of the look-up table and the predetermined algorithm is stored in a memory device.

The method of any of clauses 30-42, wherein less than 40 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 44 the method of clause 43, wherein less than 25 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 45 the method of any of clauses 30 to 44, wherein when the first drive component introduces intermittent pulses of the first fluid to create the flow front interface between the first fluid and the second fluid in the fluid conduit, the total volume of the first fluid introduced into the fluid conduit is less than a sum of a user-programmed volume and 15 milliliters.

The method of any of clauses 30-45, wherein upon actuation of the first drive member, the capacitive volume of the first fluid reservoir increases and no second fluid enters the first fluid reservoir.

Clause 47, a computer program product for preventing backflow of at least a second fluid from a second fluid reservoir into a first fluid reservoir using a fluid injector system configured to perform an injection protocol, the fluid injector system comprising a control device operatively associated with each of a first drive component configured to pressurize and inject a first fluid through a fluid conduit and at least a second drive component configured to pressurize and inject the second fluid through the fluid conduit, the fluid conduit being in selective fluid communication with the first fluid reservoir and the second fluid reservoir, wherein the computer program product comprises a non-transitory computer readable medium comprising one or more instructions that, when executed by at least one processor, cause the at least one processor to: actuating the second drive member to pressurize and inject the second fluid through the fluid conduit; and upon actuation of the second drive member, actuating the first drive member to introduce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

Clause 48 the computer program product of clause 47, wherein the at least one processor is further caused to actuate the first drive component to continue introducing intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 49, the computer program product of clause 47 or 48, wherein the at least one processor is further caused to actuate a first drive component of the two or more drive components to introduce intermittent pulses of the first fluid at a frequency or amplitude selected from the group consisting of increased frequency, decreased frequency, increased amplitude, decreased amplitude, and any combination thereof based on a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, an observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, a detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof.

Clause 50 the computer program product of any of clauses 47 to 49, wherein the at least one processor is further caused to decrease at least one of the frequency and the amplitude of the intermittent pulses of the first fluid or to change the waveform of the intermittent pulses of the first fluid, and to deliver the first fluid at a first fluid flow rate and the second fluid at a second fluid flow rate through the fluid conduit at a desired ratio of the first fluid and the second fluid.

Clause 51 the computer program product of any of clauses 47 to 50, wherein the at least one processor is further caused to monitor at least one of the pressure in the first fluid reservoir and the pressure in the second fluid reservoir during the injection of the first fluid and the second fluid to determine if a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches a first predetermined value.

Clause 52 the computer program product of clause 51, wherein, upon reaching the first predetermined value, the at least one processor is further caused to initiate a second set of intermittent pulses of the first fluid through the fluid conduit to prevent the second fluid from entering the first fluid reservoir.

Clause 53 the computer program product of any of clauses 47 to 50, wherein the at least one processor is further caused to monitor the injection pressure in the fluid conduit and determine if the injection pressure has changed by a second predetermined value.

Clause 54 the computer program product of any of clauses 47 to 50, wherein the at least one processor is further programmed or configured to calculate a predetermined injection pressure based on at least one of the programmed injection scheme and the user input information, and in response, adjust the preset waveform of the intermittent pulses.

Clause 55, the computer program product of any of clauses 47 to 54, wherein the at least one processor is further caused to continuously monitor the rate of change of the injection pressure in the fluid conduit, and in response, adjust at least one of the pulse interval, the pulse flow rate, and the pulse amount of the intermittent pulses based on a look-up table or a predetermined algorithm.

Clause 56 the computer program product of any of clauses 47 to 55, wherein when introducing intermittent pulses of the first fluid, the at least one processor is further caused to select a pulse interval from a look-up table or a predetermined algorithm.

Clause 57, the computer program product of clause 56, wherein the at least one processor is further caused to select a pulse flow rate from a look-up table or a predetermined algorithm when introducing the intermittent pulses of the first fluid.

Clause 58 the computer program product of any of clauses 47 to 57, wherein the at least one processor is further caused to select the pulse amount from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

Clause 59 the computer program product of any of clauses 56 to 58, wherein at least one of the look-up table and the predetermined algorithm is stored in a memory device.

Clause 60 the computer program product of any of clauses 47 to 59, wherein less than 40 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 61 the computer program product of clause 60, wherein less than 25 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

Clause 62 the computer program product of any of clauses 47 to 61, wherein when the first drive component introduces intermittent pulses of the first fluid to create the flow front interface between the first fluid and the second fluid in the fluid conduit, the total volume of the first fluid introduced into the fluid conduit is less than a sum of a user-programmed volume and 15 milliliters.

Clause 63 the computer program product of any of clauses 47 to 62, wherein when the first drive component is actuated, the capacitive volume of the first fluid reservoir increases and no second fluid enters the first fluid reservoir.

Further details and advantages of the various examples described in detail herein will become apparent upon reading the following detailed description of the various examples in conjunction with the accompanying drawings.

Drawings

Fig. 1 is a perspective view of a multi-fluid delivery system according to one example of the present disclosure;

fig. 2 is a perspective view of a multi-patient disposable kit (MUDS) for use with the multi-fluid delivery system of fig. 1;

FIG. 3 is a perspective view of the connection interface prior to connecting the Single Use Disposable Set (SUDS) connector with the multi-fluid delivery system;

FIG. 4 is a schematic diagram of an electronic control system of a multi-fluid delivery system according to some examples;

fig. 5 is a perspective view of a multi-fluid delivery system according to another example of the present disclosure;

FIG. 6A is a graph showing pressure versus time for a first fluid and a second fluid, where the first fluid and the second fluid produce the same pressure over time;

FIG. 6B is a graph showing pressure of a first fluid and a second fluid over time, wherein the pressure of the first fluid and the second fluid differ over time;

FIG. 7 is a representation of a portion of a prior art fluid injector system;

FIG. 8 is a representation of a portion of a fluid injector system according to an aspect of the disclosed concept;

FIG. 9 is a graphical representation of motor speed versus time during a cycle of operation of the fluid injector system of FIG. 8, in accordance with aspects of the disclosed concept;

FIG. 10 is an enlarged view of a portion of the fluid injector system of FIG. 8;

FIG. 11 is a portion of a lookup table in accordance with aspects of the disclosed concept;

FIG. 12 is a flow chart of an exemplary method of preventing backflow in a fluid injector system in accordance with an aspect of the disclosed concept;

13-18 are other graphical representations of motor speed versus time during a cycle of operation of the fluid injector system of FIG. 8 in accordance with other aspects of the disclosed concept; and is also provided with

Figures 19-25 are other graphical representations of motor speed, saline and contrast pressure rates and flow rates during an infusion protocol in accordance with the disclosed concepts.

Detailed Description

For purposes of the following description, the terms "upper," "lower," "right," "left," "vertical," "horizontal," "top," "bottom," "transverse," "longitudinal," and derivatives thereof shall relate to the disclosure as drawn. The term "proximal" when used with respect to a syringe of a multi-patient disposable set refers to the portion of the syringe closest to the plunger for delivering fluid from the syringe.

Spatial or directional terms, such as "left", "right", "inner", "outer", "upper", "lower", and the like, should not be construed as limiting, as the invention may assume a variety of alternative orientations.

In all cases, all numbers used in the specification and claims are to be understood as modified by the term "about". The term "about" refers to a range of plus or minus ten percent of the stated value.

The terms "at least one" and "at least one" as used herein are synonymous with "one or more". For example, the phrase "at least one of A, B and C" refers to any one of A, B and C, or any combination of any two or more of A, B and C. For example, "at least one of A, B and C" comprises one or more individual a; or one or more individual B; or one or more individual C; or one or more a and one or more B; or one or more a and one or more C; or one or more B and one or more C; or one or more of all A, B and C. Similarly, as used herein, the term "at least two" is synonymous with "two or more". For example, the phrase "at least two of D, E and F" means any combination of any two or more of D, E and F. For example, "at least two of D, E and F" include one or more D and one or more E; or one or more D and one or more F; or one or more E and one or more F; or one or more of all D, E and F.

It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary examples of the disclosure. Accordingly, the particular dimensions and other physical characteristics related to the examples disclosed herein are not to be considered as limiting.

When used in reference to a fluid reservoir such as a syringe, rolling diaphragm or multi-syringe disposable set, the term "distal" refers to the portion of the fluid reservoir that is closest to the patient. When used in reference to a fluid reservoir such as a syringe, rolling diaphragm, or multi-syringe disposable set, the term "proximal" refers to the portion of the fluid reservoir closest to the injector system.

The term "open" as used in reference to the fluid delivery member means that the fluid reservoir is fluidly connected to an outlet to atmospheric pressure or to the vascular system of the patient, for example, through an orifice or an open end of a tubing member or conduit. In an open system, fluid flow may be restricted or limited, for example, by forcing fluid through a small diameter fluid path, which may be determined by physical parameters of the system and fluid (e.g., tubing diameter, fluid path constriction, applied pressure, viscosity, etc.). When used in reference to a fluid delivery component, the term "closed" or "closable" refers to a fluid reservoir having at least one state in which the component is not in fluid communication with an outlet at atmospheric pressure or connected to the vascular system of a patient, or in which fluid in the fluid reservoir is fluidly isolated, e.g., where fluid flow is stopped by a valve (e.g., a stopcock, a high-pressure valve, a pinch valve, etc.) that closes a fluid path.

Referring to the drawings, wherein like reference numerals refer to like parts throughout the several views, one embodiment of the present disclosure generally relates to a multi-fluid medical injector/injector system 100 (hereinafter "fluid injector system 100") that may, in certain embodiments, contain a multi-patient disposable set (MUDS) 130 configured for delivering fluids to a patient using a single-use disposable set (SUDS) 190 connector, and in other embodiments may contain two or more disposable fluid reservoirs or syringes that may be discarded after a single injection procedure or a specific number of injection procedures. The fluid injector system 100 may include a plurality of components, as described separately herein. In general, the fluid injector system 100 shown in fig. 1-3 has a powered injector or other drug delivery device and a fluid delivery kit intended to be associated with an injector to deliver one or more fluids under pressure from one or more multi-dose containers to a patient, as described herein. The various devices, components, and features of the fluid injector system 100 and the fluid delivery kit associated therewith are also described in detail herein. Although various embodiments of methods and processors are shown with reference to injector systems having multiple use disposable sets ("MUDS") and single use disposable sets ("SUDS") configurations in fig. 1-3, the present disclosure is not limited to such injector systems and may be used in other syringe-based injector systems, such as, but not limited to, U.S. patent nos. 7,553,294, 7,563,249, 8,945,051, 9,173,995, 10,124,110; and injector systems described in U.S. application Ser. Nos. 15/305,285, 15/541,573, 15/568,505, the disclosures of each of which are incorporated herein by reference in their entirety.

Referring to fig. 1, a fluid injector system 100 according to one embodiment includes an injector housing 102, the injector housing 102 having opposite lateral sides 104, a distal or upper end 106, and a proximal or lower end 108. The housing 102 encloses the various mechanical drive components, the electrical and power components required to drive the mechanical drive components, and control components, such as electronic storage and electronic control device(s) (hereinafter), for controlling the operation of a reciprocally movable piston 103 (not shown) associated with the fluid injector system 100 described herein. Such pistons 103 may be reciprocally operable via electromechanical drive components such as motor driven ball screws, voice coil actuators, rack and pinion systems, linear motors, and the like. In some examples, at least some of the mechanical drive, electrical and power components, and control components may be provided on the base 110.

With continued reference to fig. 1, the fluid injector system 100 may have at least one door 116, with the at least one door 116 enclosing at least portions of the MUDS, mechanical drive components, electrical and power components, and control components.

The fluid injector system 100 may include at least one bulk fluid connector 118 to connect with at least one bulk fluid source 120. In some examples, a plurality of bulk fluid connectors 118 may be provided. For example, as shown in the fluid injector embodiment illustrated in fig. 1, three body fluid connectors 118 may be provided side-by-side or in other arrangements. In some examples, the at least one bulk fluid connector 118 may include a spike configured for removable connection to at least one bulk fluid source 120, such as a vial, bottle, or bag. The at least one bulk fluid connector 118 may be formed on a multiple use disposable set ("MUDS") as described herein. The at least one bulk fluid source 120 may be configured to receive a medical fluid, such as saline, imaging contrast, or other medical fluid, for delivery to a patient by the fluid injector system 100.

With continued reference to fig. 1, an embodiment of the fluid injector system 100 may include one or more user interfaces 124, such as a Graphical User Interface (GUI) display window. The user interface 124 may display information related to a fluid injection process involving the fluid injector system 100, such as patient information, a programmed injection protocol, injection status or progress, current flow rate, fluid pressure, and volume remaining in at least one bulk fluid source 120 connected to the fluid injector system 100, and may be a touch screen GUI that allows an operator to input commands and/or data for operation of the fluid injector system 100, as well as receive operator commands from a remote input station or display. While the user interface 124 is shown on the injector housing 102, such user interface 124 may also be in the form of a remote display, or the fluid injector system 100 may additionally have a remote display that is wired or wirelessly linked to the housing 102 and the control and mechanical elements of the fluid injector system 100, such as in a remote room designed to shield the user from exposure to x-rays. In some examples, the user interface 124 may be a tablet computer that is removably connected to the housing 102 and communicates with the housing 102 with a wired or wireless link. Additionally, the fluid injector system 100 and/or the user interface 124 may include at least one control key 126 for tactile operation by a care operator of the fluid injector system 100. In some examples, at least one control key 126 may be part of a keyboard to input commands and/or data by an operator. The at least one control key 126 may be hardwired to the electronic control device(s) associated with the fluid injector system 100 to provide direct input to the electronic control device(s). The at least one control key 126 may also be a graphical portion of the user interface 124, such as a touch screen. In either arrangement, at least one control key 126 desirably provides the care operator of the fluid injector system 100 with certain individual control features, such as, but not limited to: (1) Confirming that the multi-patient disposable set has been loaded or unloaded; (2) selecting or programming an injection scheme; (3) fill/purge fluid injector system 100; (4) Inputting information and/or data related to the patient and/or the injection procedure; (5) pre-fluid injector system 100; and (6) initiate/stop the injection process. The user interface 124 and/or any electronic processing unit associated with the fluid injector system 100 may be connected, either wired or wirelessly, to an operation and/or data storage system, such as a hospital network system.

Referring to fig. 2, the embodiment of the fluid injector system 100 shown in fig. 1 may include a MUDS 130, the MUDS 130 being removably connected to the fluid injector system 100 to deliver one or more fluids from one or more bulk fluid sources 120 to a patient. Examples and features of embodiments of the MUDS are further described in PCT international publication No. wo 2016/112163, filed 1/7 in 2016, the disclosure of which is incorporated herein by reference in its entirety. The MUDS 130 may contain one or more fluid reservoirs 132, such as one or more syringes. As used herein, the term "fluid reservoir" refers to any container capable of containing and delivering a fluid, for example, during a fluid injection process, including, for example, syringes, rolling diaphragms, pumps, compressible bags, and the like. The fluid reservoir may contain at least a portion of the internal volume (such as one or more tubing lengths) of the fluid passageway in fluid communication with the interior of the fluid reservoir, including a portion of the fluid passageway that remains in fluid communication with the fluid reservoir after the system is closed or fluidly isolated from the remainder of the fluid passageway. In some examples, the number of fluid reservoirs 132 may correspond to the number of bulk fluid sources 120. For example, referring to fig. 2, muds 130 has three syringes 132 arranged side-by-side such that each syringe 132 may be fluidly connected to one or more of the corresponding three bulk fluid sources 120. In some examples, one or more bulk fluid sources 120 may be connected to one or more injectors 132 of the MUDS 130. Each syringe 132 may be fluidly connected to one of the bulk fluid sources 120 by a corresponding bulk fluid connector 118 and an associated MUDS fluid path 134. The MUDS fluid path 134 may have a spike element connected to the bulk fluid connector 118 and a fluid inlet line 150. In some examples, bulk fluid connector 118 may be provided directly on MUDS 130.

With further reference to fig. 2, the muds 130 is removably connectable to the housing 102 of the fluid injector system 100. As will be appreciated by one of ordinary skill in the art, it may be desirable to construct at least a portion of the MUDS 130 from a transparent medical grade plastic in order to visually verify that a fluid connection has been established with the fluid injector system 100 or that air has been removed from the fluid reservoir. Visual verification is also desirable to confirm the general absence of air bubbles within various fluid connections, for example, after performing an air removal protocol such as that described herein. Various optical sensors (not shown) may also be provided to detect air in the fluid line or fluid reservoir during the priming operation.

With continued reference to fig. 2, the muds 130 may include one or more valves 136, such as stopcocks, to control which medical fluid or combination of medical fluids is pumped from the multi-dose bulk fluid source 120 (see fig. 1) into the fluid reservoirs 132 and/or delivered from each fluid reservoir 132 to the patient. In some examples, one or more valves 136 may be provided on the distal ends of the plurality of syringes 132 or on the manifold 148. Manifold 148 may be in selectable fluid communication with the interior volume of syringe 132 via valve 136. The interior volumes of the syringes 132 may be in selectable fluid communication with a first end of a MUDS fluid path 134 via a valve 136, the first end of the MUDS fluid path 134 connecting each syringe 132 to a corresponding bulk fluid source 120. An opposite second end of MUDS fluid path 134 may be connected to a respective bulk fluid connector 118, bulk fluid connector 118 configured for fluid connection with bulk fluid source 120. Depending on the position of the one or more valves 136, fluid may be drawn into the interior volume of the one or more syringes 132 or may be delivered from the interior volume of the one or more syringes 132. In a first position, such as during filling of the syringe 132, the one or more valves 136 are oriented such that fluid flows from the bulk fluid source 120 into the desired syringe 132 through the fluid inlet line 150 (such as the MUDS fluid path). During the filling process, the one or more valves 136 are positioned such that fluid flow through the one or more fluid outlet lines 152 or manifolds 148 is blocked or closed. In a second position, such as during a fluid delivery process, fluid from one or more syringes 132 is delivered to manifold 148 through one or more fluid outlet lines 152 or syringe valve outlet ports. During the delivery process, the one or more valves 136 are positioned such that fluid flow through the one or more fluid inlet lines 150 is blocked or closed. In the third position, the one or more valves 136 are oriented such that fluid flow through the one or more fluid inlet lines 150 and the one or more fluid outlet lines 152 or the manifold 148 is blocked or closed. Thus, in the third position, each of the one or more valves 136 isolates the corresponding syringe 132 and prevents fluid from flowing into and out of the interior volume of the corresponding syringe 132. Thereby, each of the one or more syringes 132 and the corresponding valve 136 define a closed system.

One or more valves 136, fluid inlet lines 150, and/or fluid outlet lines 152 may be integrated into the manifold 148 or in fluid communication via the manifold 148. The one or more valves 136 may be selectively positionable to the first position or the second position by manual or automatic manipulation. For example, an operator may position one or more valves 136 to a desired position for filling, fluid delivery, or to a closed position. In other examples, at least a portion of the fluid injector system 100 is operable to automatically position one or more valves 136 to a desired position for filling, fluid delivery, or to a closed position based on input from an operator or a protocol in a system controller.

Having generally described the components of the fluid injector system 100 and MUDS 130, the structure and method of use of the single-use disposable set 190 (SUDS) and its interaction with the MUDS 130 will now be described.

Referring to fig. 3, in accordance with the described embodiment, the fluid injector system 100 has a connection port 192, the connection port 192 being configured to form a releasable fluid connection with at least a portion of the SUDS 190. In some examples, the connection port 192 may be formed on the MUDS 130. As described herein, the SUDS 190 may be connected to a connection port 192, the connection port 192 being formed on at least a portion of the MUDS 130 and/or the housing 102. Desirably, the connection between the SUDS 190 and the connection port 192 is a releasable connection to allow the SUDS 190 to be selectively disconnected from the connection port 192 and connected to the connection port 192. In some examples, SUDS 190 may be disconnected from connection port 192 and discarded after each fluid delivery procedure, and a new SUDS 190 may be connected to connection port 192 for a subsequent fluid delivery procedure. SUDS 190 may be used to deliver one or more medical fluids to a patient by SUDS fluid line 208, SUDS fluid line 208 having a distal end that may be selectively disconnected from the body of SUDS 190 and connected to a patient catheter. Other examples and features of SUDS 190 are described in U.S. patent publication No.2016/0331951, filed 7/2016, the disclosure of which is incorporated herein by reference.

Referring to fig. 4, an electronic control device 900 may be associated with the fluid injector system 100 to control the filling and delivery operations of the fluid injector 100. In some examples, electronic control device 900 may control the operation of various valves, stopcocks, piston elements, and other elements to affect a desired gas/air removal, filling, and/or delivery process. For example, electronic control device 900 may include a variety of discrete computer-readable media components. For example, the computer readable medium may include any medium that is accessible by the electronic control device 900, such as volatile media, non-volatile media, removable media, non-removable media, temporary media, non-temporary media, and the like. As other examples, the computer-readable medium may comprise a computer storage medium, such as a medium implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules, or other data; random Access Memory (RAM), read Only Memory (ROM), electrically Erasable Programmable Read Only Memory (EEPROM), flash memory, cloud storage media, or other memory technology; solid state memory, cloud memory, CD-ROM, digital Versatile Disk (DVD), or other optical disk storage; magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices; or any other medium that can be used to store the desired information and that can be accessed by electronic control device 900. Additionally, the computer-readable medium may contain communication media such as computer-readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave or other transport mechanism, and include any information delivery media, wired media (such as a wired network and direct-wired connection), and wireless media (such as acoustic signals, radio frequency signals, optical signals, infrared signals, biometric signals, bar code signals, and the like). Of course, any combination of the above should also be included within the scope of computer-readable media.

The electronic control device 900 also includes a system memory 908 having computer storage media in the form of volatile and nonvolatile memory such as ROM and RAM. A basic input/output system (BIOS), having suitable computer-based routines, assists in transferring information between elements within the electronic control device 900 and is typically stored in ROM. The RAM portion of the system memory 908 typically contains data and program modules that are immediately accessible to the processor 904 or that are run by the processor 904, e.g., an operating system, application programming interfaces, application programs, program modules, program data, and other instruction-based computer readable code.

With continued reference to fig. 4, the electronic control device 900 may also include other removable or non-removable, volatile or nonvolatile, transitory or non-transitory computer storage media products. For example, electronic control device 900 may include a non-removable memory interface 910 that communicates with hard disk drive 912 (e.g., non-removable, non-volatile magnetic media) and controls hard disk drive 912; and a removable, non-volatile memory interface 914 that communicates with and controls: a magnetic disk drive unit 916 that reads from and writes to a removable, nonvolatile magnetic disk 918, an optical disk drive unit 920 that reads from and writes to a removable, nonvolatile optical disk 922 such as a CD ROM, a Universal Serial Bus (USB) port 921 for use with a removable memory card, etc. However, it is contemplated that other removable or non-removable, volatile or nonvolatile computer storage media may be used in the exemplary computing system environment 902 including, but not limited to, magnetic tape cassettes and floppy disks, CDs, DVDs, digital video bands, solid state RAM, solid state ROM, cloud storage, and the like. These various removable or non-removable, volatile or nonvolatile magnetic media are in communication with processor 904 and other components of electronic control device 900 via system bus 906. The drives and their associated computer storage media discussed above and illustrated in FIG. 4 provide the following storage: operating system, computer readable instructions, application programs, data structures, program modules, program data, and other instruction-based, computer readable code for electronic control device 900 (whether or not a copy of this information and data in system memory 908).

A user may enter commands, information, and data into the electronic control device 900 through some attachable or operable input device, such as the user interface 124 shown in fig. 1, via a user input interface 928. A variety of such input devices may be employed, such as microphones, trackballs, joysticks, touch pads, touch screens, scanners, and the like, including any arrangement that facilitates the input of data and information from an external source to the electronic control device 900. As discussed, these and other input devices are often connected to the processor 904 through a user input interface 928 that is coupled to the system bus 906, but may be connected by other interface and bus structures, such as a parallel interface, game port or USB. In addition, the data and information may be presented or provided to the user in an understandable form or format through some output device, such as a display 930 (visually displaying the information and data in electronic form), a printer 932 (physically displaying the information and data in printed form), a speaker 934 (audibly presenting the information and data in audible form), and so forth. All of these devices communicate with the electronic control device 900 through an output interface 936 coupled to the system bus 906. Any such peripheral output devices are contemplated for providing information and data to a user.

The electronic control device 900 may operate in a network environment 938 using a communication device 940, the communication device 940 being integrated with or remote from the electronic control device 900. The communication device 940 is operable by and communicates with other components of the electronic control device 900 via a communication interface 942. With such an arrangement, the electronic control device 900 may be connected to or otherwise communicate with one or more remote computers, such as remote computer(s) 944, which may be personal computers, servers, routers, network personal computers, peer devices, or other common network nodes, and typically contains many or all of the components described above in connection with the electronic control device 900. Using a suitable communication device 940 (e.g., modem, network interface, or adapter, etc.), computer 944 can operate within and communicate over a Local Area Network (LAN) and a Wide Area Network (WAN), but can also include other networks, such as a Virtual Private Network (VPN), an office network, a hospital network, an enterprise network, an intranet, the internet, and so forth.

As used herein, the electronic control device 900 contains or is operable to execute appropriately custom designed or conventional software to perform the processing steps of the methods of the present disclosure and to implement the systems of the present disclosure, thereby forming the specific and particular computing systems. Accordingly, the methods and systems may include one or more electronic control devices 900 or similar computing devices having computer-readable storage media capable of storing computer-readable program code or instructions that cause the processor 904 to execute, configure or otherwise implement the methods, processes and conversion data operations discussed below in connection with the present disclosure. In addition, the electronic control device 900 may be in the form of a computer-implemented method and system effective to: personal computers, personal digital assistants, portable computers, laptop computers, tablet computers, palmtop computers, mobile devices, mobile phones, servers, or any other type of computing device that has the necessary processing hardware and software to properly process data.

It will be apparent to those skilled in the art that the system may employ a database, such as a lookup table, physically located on or accessible by one or more computers, which may or may not be identical to their respective servers. For example, programming software on the electronic control device 900 may control a database physically stored on a network or other separate processor.

In some examples, the electronic control device 900 may be programmed to measure and/or monitor one or more injection parameters during an injection protocol, such as injection parameters selected from the group consisting of: the pressure of the fluid in each of the various fluid reservoirs, the pressure in the fluid conduit downstream of the fluid reservoirs, the fluid flow rate of each fluid in its entry into or exit from each of the fluid reservoirs, the fluid flow rate of the fluid in the fluid conduit, the presence of fluid flashback in the fluid conduit, the viscosity of the fluid in the fluid reservoirs and/or the fluid conduits, the temperature of the fluid in the fluid reservoirs, the speed of the driving component (such as a piston or plunger of each of the various fluid reservoirs), the pulse frequency and/or amplitude of the pulse train of the driving component, and various combinations thereof. The control device 900 may measure one or more injection parameters and/or obtain one or more injection parameters through electrical and/or mechanical communication with one or more sensors associated with the fluid injection system. Based on the measured and/or monitored injection parameters, the control device 900 may modify, adjust, initiate, or stop the corresponding operation, e.g., if the sensor reads that the injection parameters are outside of or tend to be outside of the desired range, the parameters are adjusted toward or within the desired range.

Although fig. 1-3 illustrate one example of a fluid injector system 100 and associated components and structures, it should be understood that the present disclosure is not limited to any particular type or kind of fluid injector system 100. Referring now to fig. 5, another non-limiting example of a fluid injector system 100 according to the present disclosure includes at least one fluid reservoir, such as a syringe 12, at least one piston 103 (not shown) connectable to at least one plunger 14, and a fluid control module (not shown, such as a control device 900). The at least one syringe 12 is generally adapted to interface with at least one component of the system, such as the syringe port 13. The fluid injector system 100 is generally configured to deliver at least one fluid F to a patient during an injection procedure. The fluid injector system 100 is configured to releasably receive at least one syringe 12, the at least one syringe 12 to be filled with at least one fluid F, such as contrast media, saline solution, or any desired medical fluid. The system may be a multi-syringe injector in which several syringes may be oriented side-by-side or in another spatial relationship and separately actuated by respective pistons associated with the injector. The at least one syringe 12 may be oriented in any manner, such as upright, inverted, or oriented at any angle. In another embodiment, the fluid injector 100 may interface with one or more rolling diaphragm syringes (not shown). Non-limiting examples of rolling diaphragm syringe based injectors are described in U.S. application Ser. Nos. 15/305,285 and 15/568,505, and PCT International application No. PCT/US2017/056747, the disclosures of which are incorporated herein.

With continued reference to fig. 5, the injector system 100 may be used during a medical procedure to inject at least one medical fluid F into the vasculature of a patient by driving the plunger 14 of at least one syringe 12 with a drive member, such as at least one piston 103 (not shown). The at least one piston may be reciprocally operable over at least a portion of the at least one syringe, such as the plunger 14. Once engaged, the at least one piston may move the plunger 14 toward the distal end 19 of the at least one syringe and retract the plunger 14 toward the proximal end 11 of the at least one syringe 12.

A tubing set (e.g., first and second fluid tubing 17a, 17b and a common fluid tubing 20) may be in fluid communication with the outlet port of each syringe 12 to place each syringe in fluid communication with a catheter to deliver fluid F from each syringe 12 to a catheter (not shown) inserted into a patient at a vascular access site. The first fluid conduit 17a and the second fluid conduit 17b may be connected to the common fluid conduit 20 by any suitable mechanism known in the art (e.g., Y-connector or T-connector). In certain embodiments, fluid flow from one or more syringes 12 may be regulated by a fluid control module, which may be the same or similar to the electronic control device 900, that operates various drive components, valves, stopcocks, and flow regulating structures to regulate delivery of at least one fluid to a patient based on user-selected injection parameters, such as injection flow rate, fluid pressure within each syringe, fluid flow rate in fluid tubing duration, and total injection volume. The fluid control module is generally configured to perform various functions that can assist in preventing backflow of fluid from one syringe to another syringe of the system, as will be described herein in connection with other various embodiments.

In some examples, the fluid control module may instruct the fluid injector system 100 to fill at least one syringe 12 with at least one fluid F. The fluid injector system 100 may have multiple bulk fluid sources, such as a bulk contrast fluid source and a bulk saline source, one for each syringe 12, to fill each of the syringes with the desired fluid. The at least one syringe 12 may be filled with the at least one fluid F by placing the at least one syringe 12 in fluid communication with the at least one source of fluid, and instructing the fluid injector system 100 to retract a piston removably engaged with the plunger 14 of the at least one syringe 12 from the distal end 19 of the at least one syringe toward the proximal end 11 of the at least one syringe. In certain embodiments, the fluid injector system 100 and the fluid control module may be programmed to perform an air removal protocol. As shown in fig. 5, the fluid injector system 100 may be an open system, i.e., two syringes 12 may be fluidly connected to a first fluid conduit 17a and a second fluid conduit 17b, the first fluid conduit 17a and the second fluid conduit 17b being connected to a common fluid conduit 20 without any intermediate or stopcock valves. In such an open system, a difference in fluid pressure in the first syringe relative to the fluid pressure in the second syringe may cause backflow of fluid from the higher pressure syringe into the lower pressure syringe. Such conditions, such as the flow of higher pressure contrast fluid into a lower pressure saline syringe, may result in, for example, inaccurate amounts of fluid delivered, suboptimal images from the imaging procedure, and waste of medical fluid. According to other embodiments, the fluid injector system 100 may be a closed system, for example, the distal end 19 of the syringe 12 and/or each of the first and second fluid conduits 17a, 17b may contain one or more valves or stopcocks to fluidly isolate the interior of each syringe from the other of the first and second fluid conduits 17a, 17b and the other syringe 12.

For injector systems having multiple reservoir disposables (such as fluid injector systems having two or more syringes as described and illustrated herein) configured to deliver more than one fluid type (such as contrast fluid and saline flush fluid), it is desirable to prevent inadvertent mixing of two fluids in different reservoirs. This may particularly relate to multi-patient applications, where the same reservoir(s) may be used for multiple patients over the lifetime of the disposable reservoir. For example, contrast is unintentionally mixed into the physiological saline reservoir, which may lead to unexpected patient doses during the test injection or wash-out phase. Conversely, physiological saline is unintentionally mixed into the contrast reservoir, which may lead to diluted doses, resulting in non-diagnostic or degraded quality images.

For some injectors, the orientation of the disposable may be fixed during use. For example, in some injectors, the reservoir is always oriented with the distal outlet of the reservoir facing upward. In such a reservoir arrangement, it is involved that the denser fluid enters from the top of the reservoir and continues down to any fluid mixing in the occupied fluid. Given the relative densities of contrast and saline, this means that if contrast were to enter the saline reservoir, it would sink to the bottom. Since in a vertical setting the contrast will settle at the bottom of the reservoir, it will be the fluid that was last delivered from the reservoir. Repeated flow of contrast into the saline reservoir will continue to increase the contrast percentage in the saline reservoir with each injection. The mixing of saline into the contrast reservoir will have the opposite effect. The lighter saline fluid remains trapped at the top of the contrast reservoir and only a small fraction disperses into the occupied contrast depending on the incoming fluid rate. Thus, saline will be injected at the beginning of the next imaging session, minimizing the effects of repetitive mixing over time but resulting in inaccurate contrast amounts being administered to the patient. According to other embodiments, such as the injector shown in fig. 5, the fluid injector head may be rotated so that the distal end of the syringe is generally directed in a downward direction. In this embodiment, the backflow of the denser contrast into the saline syringe will cause the contrast to pool at the distal tip of the syringe, such that when the fluid injector is programmed to inject saline, the contrast at the distal tip is injected first, resulting in overdosing and wasted contrast, and affecting the quality of the obtained image. The backflow of saline into the contrast injector will cause pooling of saline at the proximal end of the injector near the plunger, which will dilute the administered contrast agent when there is a small volume of fluid within the contrast injector, affecting the quality of the acquired image.

The reason for mixing between reservoirs is due to a phenomenon known as backflow, in which higher pressure fluid flows upstream against the flow of lower pressure fluid. Reflux is a physical phenomenon based at least in part on a pressure gradient. The basic principle is that the flow occurs in the direction of pressure drop, e.g. the flow propagates from the point of highest pressure to the point of lowest pressure. In some disposables, this pathway tends to travel from the infusion reservoir down the patient tubing set and out of the catheter. The reservoir is the highest pressure point, as the pressure in the reservoir is created by the draining of the fluid by the driving member. The strength of the pressure depends on the fluid viscosity, flow rate, mechanical relaxation of the injector components under load, expansion of the syringe and tubing materials under fluid pressure, and downstream impedance (i.e., without limitation, ID of the syringe outlet, tubing gauge, and tubing set ID). If both reservoirs are open at the same time, there is a risk of backflow if the pressure between the two reservoirs is different. The reservoir with the lowest pressure will be prone to introducing higher pressure fluid via backflow through the connected tubing set. Reflux via this mechanism may also occur or be exacerbated by the compliant nature of the reservoir (complex nature), which expands in volume with increased pressure and load on the mechanical components of the system. As previously mentioned, the risk of inadvertent mixing of the fluids only exists when two of the at least three reservoirs are open to the patient line in the manifold.

Fig. 6A is a graph 1000 showing pressure versus time of a first fluid 1002, such as contrast, and a second fluid 1004, such as saline, wherein the first and second fluids 1002, 1004 produce the same pressure over time. It should be appreciated that when the fluid injector system delivers fluid according to the pressure profile, the likelihood of one of the first fluid 1002 or the second fluid 1004 flowing back into the reservoir containing the other of the first fluid 1002 or the second fluid 1004 is relatively low and/or zero. In contrast, fig. 6B is a graph 1010 showing pressure versus time of a first fluid 1012, such as contrast, and a second fluid 1014, such as saline, wherein the first fluid 1012 and the second fluid 1014 produce different pressures over time. In fluid injector systems having a pressure profile such as that shown in fig. 6B, it is known that undesirable backflow from the higher pressure contrast reservoir into the lower pressure saline reservoir occurs when there is a pressure differential Δp between the reservoirs. This is best shown in fig. 7, which illustrates portions of a prior art fluid injector system 1100. As shown, a lower pressure first fluid, such as saline 1110, is contained in a first fluid reservoir 1112, while a second fluid, such as contrast 1114, is contained in a second fluid reservoir 1116. In addition, as shown, the fluid conduit 1101 may provide a fluid pathway between the first and second fluid reservoirs 1112, 1116 during a condition known as dual flow, wherein both the first and second fluid reservoirs 1112, 1116 are open and a mixture of contrast and saline of a particular ratio flows simultaneously to the patient line. As shown in fig. 7, due to differences in pressure distribution between the first fluid reservoir 1112 and the second fluid reservoir 1116, see, for example, fig. 6B, wherein contrast 1114 corresponds to pressure curve 1012 and saline 1110 corresponds to pressure curve 1014, contrast 1114 from the second fluid reservoir 1116 has undesirably "reflowed" and entered the first fluid reservoir 1112.

The dual flow phase may be programmed to a volume ratio from, for example, 1% contrast/99% saline to 99% contrast/1% saline. Thus, there is a wide range of pressure gradients that can be created between the first, saline reservoir and the second, contrast fluid reservoir. Depending on certain flow conditions, the reflux may be considered as mixing of contrast into the saline reservoir, as density differences will cause contrast to settle to the bottom and accumulate over time. In certain embodiments, when the dual flow ratio is 95% to 99% contrast to 5% to 1% saline for the dual flow phase, this type of mixing is common because the contrast flow rate is much greater than the saline flow rate and thus creates a large pressure differential in the contrast reservoir relative to the saline reservoir.

According to various embodiments, the dual-flow phase may be the first programming phase of injection, or may follow the contrast phase, the saline phase, a different dual-flow phase, or the delay phase. In some embodiments, the programmed protocol sequence may be a contrast phase followed by a dual flow phase followed by a saline phase. In this case, the contrast reservoir will inject and create some steady state pressure for the contrast phase. As the dual flow phase begins, the saline reservoir will then open and begin to ramp up pressure as saline flow is initiated. The ramping pressure in the saline reservoir may include moving the drive member to pressurize the fluid, along with compensating for the volumetric expansion of the reservoir due to compliant absorption (uptake) and mechanical relaxation absorption. However, if the saline pressure is open to the outlet line at atmospheric pressure or a pressure below the contrast phase and the contrast has a greater pressure, such as that resulting from the pressure of the previous phase, a backflow into the saline reservoir through the fluid conduit may occur while the saline reservoir ramps to a steady state pressure. To prevent this, one solution is to use pressure equalization, for example by pre-pressurizing the saline reservoir to ensure that at the end of the contrast phase and at the beginning of the dual-flow phase, the pressure in the saline reservoir is substantially equal to the contrast pressure. Since saline will dilute the contrast during the dual flow phase, the pressure in the system will drop due to the reduced viscosity of the contrast/saline mixture relative to the contrast, and there will be no increase in pressure to drive the reflux.

In some embodiments, if the dual flow phase is the first programming phase of injection or after a saline phase, a delay phase, or a contrast phase of less than 20mL volume, the saline may not have enough time to pressure equalize to the contrast pressure. Therefore, the risk of a faster rise in contrast pressure than normal saline is likely, and additional logic must be implemented to prevent reflux. In these embodiments, one way to prevent reflux is to ensure that the saline pressure is above contrast during a brief rise in pressure to steady state. However, it is difficult to ensure higher saline pressure for a dual flow ratio of greater than 50% contrast, so the contrast piston is delivering fluid faster than the saline piston. Another approach may be to use pulses of saline driving means to create a turbulent, flow front interface at the fluid conduit, thereby preventing contrast flow through the turbulent flow front and into the saline syringe.

To combat this observed backflow between the high pressure and lower pressure reservoirs, a behavior referred to herein as micropressure fluctuations or pulses may be achieved in accordance with various embodiments of the present disclosure. For example, an improved fluid injector system 1200 configured to perform an injection protocol according to various embodiments of the disclosed concepts is partially shown in fig. 8. As shown, the fluid injector system 1200 includes a control 1202 (shown in simplified form) operatively associated with each of two or more drive components 1204, 1205 (partially shown in simplified form in fig. 8). The drive components 1204, 1205 are configured to pressurize and inject a first fluid (e.g., without limitation, saline 1210) from a first fluid reservoir 1212 through a fluid conduit 1201, and to pressurize and inject at least a second fluid (e.g., without limitation, contrast 1214) from a second fluid reservoir 1216 through the fluid conduit 1201, the fluid conduit 1201 being in selective fluid communication with the first fluid reservoir 1212 and at least the second fluid reservoir 1216. The control device 1202 includes at least one processor 1203 (shown in simplified form in fig. 8) programmed or configured to actuate the second drive member 1205 to pressurize and inject contrast 1214 through the fluid conduit 1201 and, upon actuation of the second drive member 1205, actuate the first drive member 1204 to induce intermittent pulses of saline 1210 to create a turbulent, flow wavefront interface 1211 between the saline 1210 and contrast 1214 in the fluid conduit 1201, thereby preventing backflow of contrast 1214 through the fluid conduit 1201 into the first fluid reservoir 1210. In other words, the flow wavefront interface 1211 acts as a physical fluid barrier with turbulence, preventing backflow of contrast 1214 into the first fluid reservoir 1212.

In addition, a temporary pulse increase in saline flow rate creates an increased pressure in the first fluid reservoir 1210, at least temporarily reducing the strength of the pressure gradient. Accordingly, when the first drive component 1204 is actuated, the capacitive volume of the first fluid reservoir 1210 increases (due to the reservoir expanding under pressure) and the pressure of the first fluid increases without contrast 1214 flowing back through the flow wavefront interface 1211 from within the fluid conduit 1201 into the first fluid reservoir 1210. Furthermore, during delivery of intermittent pulses, there may be at least three parameters that may be controlled, such as pulse spacing (e.g., time between pulses, pulse frequency), pulse flow rate (e.g., flow rate of pulses, pulse amplitude), and pulse quantity (e.g., effective duration of pulses), which are discussed in more detail herein.

Fig. 9 shows a graphical representation 1300 of motor speed versus time during operation of the fluid injector system 1200 (fig. 8). It should be appreciated that the implementation of micropressure fluctuations uses the programmed flow rate of physiological saline 1210 during the dual flow phase and introduces intermittent pulses of increasing flow rate. These pulses create turbulence in the fluid path at the flow front interface 1211 and create rapid pressure generation to prevent backflow from occurring. Accordingly, the micropressure fluctuations take a programmed flow rate and intermittently change it to create turbulence and higher pressure in the first fluid reservoir 1212 and in some embodiments in the portion of the fluid conduit 1201 adjacent to the first fluid reservoir 1212 to counter reflux of contrast due to the pressure differential. Taking part in, for example, the enlarged view of fig. 10, which shows a flow wavefront interface 1211 between saline 1210 and contrast 1214 in fluid conduit 1201 due to intermittent pulsing of the drive component of first fluid reservoir 1212.

Referring again to fig. 8, it should be appreciated that the processor 1203 may actuate the first drive component 1204 to continue to introduce intermittent pulses of saline 1210 until the pressure of the saline 1210 reaches substantially the same pressure as the pressure of the contrast 1214 (i.e., no pressure differential exists between the first reservoir 1212 and the second reservoir 1216). In an exemplary embodiment, less than 40 milliliters of saline 1210 may be introduced into the fluid conduit 1201 before the pressure of the saline 1210 reaches substantially the same pressure as the contrast 1214. In another exemplary embodiment, less than 25 milliliters of saline 1210 may be introduced into the fluid conduit 1201 before the pressure of the saline 1210 reaches substantially the same pressure as the pressure of the contrast 1214. The volume of saline 1210 required to achieve pressure equalization may depend, for example, on one or more of the following: fluid viscosity, desired dual flow ratio, contrast pressure, speed of the drive member, geometry of the fluid path containing the attached catheter, and combinations thereof. The processor 1203 may further actuate the first drive component 1204 to introduce intermittent pulses of saline 1210 as a frequency or amplitude of one of an increased frequency, a decreased frequency, an increased amplitude, a decreased amplitude, and any combination thereof based on at least one of a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, a difference in observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof. In addition, the processor 1203 may reduce intermittent pulses of saline 1210 and deliver saline 1210 at a first fluid flow rate and contrast 1214 at a second fluid flow rate through the fluid conduit 1201 at a desired ratio of saline 1210 to contrast 1214.

Logic for individual pulse behavior may be determined from a processor-operated algorithm or look-up table 1400. Referring to, for example, fig. 11, a portion of a look-up table 1400 of input parameters based on ratio and flow rate of a dual stream phase program is shown. The logic of the individual pulse behavior may also be determined from a predetermined algorithm that determines the pulse scheme based on injection parameters entered by a user and/or stored in a saved injection scheme, for example. Suitable examples of injection parameters include a programmed flow rate, a programmed volume, a type of contrast used, an irrigation solution used, a dual flow ratio, and/or a catheter size. Accordingly, when intermittent pulses of saline 1210 are introduced, the processor 1203 may select one or more of pulse interval, pulse flow rate, and pulse amount from a look-up table (e.g., table 1400, shown in fig. 11) or a predetermined algorithm. Additionally, table 1400 and/or predetermined algorithms may be stored in a memory device associated with the processor. According to other embodiments, the processor 1203 may also continuously monitor the rate of change of the injection pressure in the fluid conduit 1201 and, in response, adjust at least one of the pulse interval, pulse flow rate, and pulse quantity of the intermittent pulses based on the look-up table 1400 or a predetermined algorithm.

Further, according to some embodiments, after reaching the steady state flow profile, the processor 1203 may monitor at least one of the pressure 1212 in the first fluid reservoir and the pressure 1216 in the second fluid reservoir during the injection of the physiological saline 1210 and contrast 1214 to determine if the difference between the pressure 1212 in the first fluid reservoir and the pressure 1216 in the second fluid reservoir reaches a first predetermined value after reaching the steady state. In addition, if and when the first predetermined value is reached, the processor 1203 may restart or initiate a new protocol of intermittent pulses of saline 1210 through the fluid conduit 1201 to prevent contrast 1214 from entering the first fluid reservoir 1212. In certain embodiments, the processor 1203 may continue to monitor the injection pressure in the fluid conduit 1201 and determine whether the injection pressure in the fluid conduit 1201 changes by a second predetermined value. In yet another embodiment, the processor 1203 may continue to monitor the difference in pressure 1212 in the first fluid reservoir and pressure 1216 in the second fluid reservoir, and if Δp reaches the first predetermined value a second time or if the injection pressure in the fluid conduit 1201 reaches the first predetermined pressure a second time, the processor may initiate again the protocol of intermittent pulses of the saline drive component until steady state is again reached. In yet another embodiment, the processor 1203 may not need to determine whether a first predetermined value of the pressure 1212 in the first fluid reservoir and the pressure 1216 in the second fluid reservoir is reached or whether a first predetermined value of the pressure in the fluid conduit 1201 is reached before initiating a subsequent pulsing scheme or sequence. According to these embodiments, the processor 1203 may extrapolate and calculate values towards a first predetermined value based on the trend of Δp of the fluid reservoir or the pressure in the fluid conduit 1201, for example by using a predictive algorithm, and may thus initiate a subsequent pulsing scheme based on the calculated trend before reaching the first predetermined value. It should be appreciated that in suitable embodiments, it is not required to monitor Δp between the first fluid reservoir 1212 and the second fluid reservoir 1216, but rather the pulsing scheme may be based on a measurement of a single injection pressure in the patient line. In addition, the predetermined pulse sequence may be identified for any combination of programmed dual flow rates, volumes, flow rates, and/or injection parameters.

Note that while intermittent pulses of saline 1210 are delivered, pulse-on (see, e.g., pulse-on 1302 shown in fig. 9) is an increase in the programmed flow rate (see, e.g., programmed flow rate 1304 shown in fig. 9) and thus can potentially result in over-delivery of saline 1210 or under-delivery of contrast 1214. In one exemplary embodiment, while the first drive component 1204 introduces intermittent pulses of saline 1210 to create a flow wavefront interface 1211 between the saline 1210 in the fluid conduit 1201 and the contrast 1214, the total volume of saline 1210 introduced is less than the sum of the user-programmed volume and 15 milliliters. From a user perspective, this over-delivery of saline is generally undesirable as it may require more saline volume to be available or required to be infused. To account for this potential saline overdose, a pulsed off (pulse-off) flow rate (see, e.g., pulsed off flow rate 1306 of fig. 9) (e.g., time when the flow rate does not increase) may reduce the saline flow rate below the programmed flow rate. The decrease in flow rate may thus counter at least part of the period of increased flow rate, resulting in that the saline delivery volume may be approximately equal to the programmed volume. The net difference between the period that the pulse-on flow rate 1302 is used to program the flow rate 1304 and the period that the pulse-off flow rate 1306 is used to program the flow rate 1304 identifies the volume of over-and under-delivery during the micro-pressure fluctuations. For example, in fig. 9, it should be understood that the trapezoid defined by the curve above the programming flow rate 1304 during the pulse sequence is illustrated as representing the amount of saline 1210 delivered, while the trapezoid defined by the curve below the programming flow rate 1304 during the pulse sequence is illustrated as representing the amount of saline 1210 not delivered. Accordingly, the theoretical expected excess delivered saline volume for each regimen may then be calculated based on the area between the programmed flow rate 1304 and the pulse on flow rate 1302/pulse off flow rate 1306 curves. In addition, intermittent pulses can be optimized to minimize and/or eliminate excessive delivery of saline.

It should also be appreciated that intermittent pulses may occur only during the first 25 milliliters of injection, which has been considered one of the portions of injection that are at risk of reflux. In addition, once the fluid injector system 1200 reaches a steady state for injection, the pressure differential between the first fluid reservoir 1212 and the second fluid reservoir 1216 has stabilized. In the absence of a pressure differential (Δp) between the first fluid reservoir 1212 and the second fluid reservoir 1216, there is no driving force for backflow, and the pulse may be reduced or even stopped. However, in some embodiments, atypical injection processes may occur, wherein adverse events occur in the middle of injection, resulting in a brief increase in pressure. This may be caused, for example, by extravasation (extravasation) of a catheter, kinking (kinking), kinking of a tubing set, etc. To prevent backflow caused by pressure increases in between these injections, the fluid injector system 1200 may monitor the pressure throughout the injection in a circuit executing predetermined logic. The predetermined logic may comprise the steps of: 1) setting the counter equal to zero, 2) setting the timer to 500 milliseconds, 3) storing the current pressure of the system, 4) comparing the pressure to the system pressure stored at the beginning at the end of the 500 millisecond timer, 5) incrementing the counter by one if the pressure has increased by 5psi or more for that duration, resetting the counter to 0 if the pressure has not increased by 5psi or more for that duration, 6) repeating steps 2-5 until the counter reaches 3 or the end of the injection phase, 7) if the counter reaches 3, triggering a pulsing action to perform 100 milliseconds, checking the pressure every 100 milliseconds, and continuing pulsing 100 milliseconds if the pressure has increased by 1 psi. The pressure check is continued until there is no pressure rise of 1psi or more for 100 milliseconds. 5psi has been considered the maximum pressure change that the fluid injector system 1200 can withstand without backflow occurring. This value (known as system elasticity) and the length of the fluid path tubing will vary from system to system.

This logic ensures that the system protects the saline reservoir from contrast contamination even under adverse event conditions.

As shown in fig. 12, in accordance with other embodiments of the present disclosure, a method 1500 is provided for preventing backflow of a second fluid from a second fluid reservoir into a first fluid reservoir in a fluid injector system configured to perform an injection protocol. The method 1500 may comprise the steps of: providing a control device operably associated with a first drive component configured to pressurize and inject a first fluid through a patient fluid conduit and at least a second drive component configured to pressurize and inject at least a second fluid from a second fluid reservoir through the fluid conduit; a second one of the two or more drive members is actuated to pressurize and inject a second fluid through the fluid conduit, and upon actuation of the second drive member, a first one of the two or more drive members is actuated to introduce intermittent pulses of the first fluid to create a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir. According to other embodiments, the present disclosure may include similarly modified methods of the various processor-initiated steps described herein.

13-18 illustrate graphical representations 1600 of motor speed versus time during operational cycles of the fluid injector system 1200 of FIG. 8 using various non-limiting pulsing schemes in accordance with other aspects of the disclosed concept,1610. 1620, 1630, 1640 and 1650. It should be appreciated that the behavior of the intermittent pulses may have any combination of parameters. For example, in fig. 13, t ₁ 、t ₂ 、T、A ₁ And A ₂ May correspond to the time between pulses, the time above the target, the time below the target, the total pulse duration, the amplitude of the pulse above the target, and the amplitude of the pulse below the target, respectively. As shown in the graphical representations 1610, 1620, 1630, 1640, and 1650 of fig. 14-18, any and all of these parameters may be modified to produce different pulse behaviors, sequences, and schemes. In addition, it should be understood that other suitable alternative pulse patterns are contemplated herein. For example and without limitation, graphical representations of pulses having different gradients are contemplated, and the pulses may also be more jagged (e.g., shorter times at full pulse flow). Further, sinusoidal pulse patterns with more rounded vertices are contemplated herein, such as due to a release of strain on the piston member or a loss or increase in momentum of the driving member at the beginning and end of the pulse.

Fig. 19-25 illustrate other graphical representations 1700, 1710, 1720, 1730, 1740, 1750, and 1760 of motor speed (fig. 19, 20, and 25), saline and contrast pressure (fig. 21 and 24), and flow rate (fig. 22 and 23) during the course of an injection protocol according to an embodiment of the fluid injector system 1200. In each graphical representation 1700, 1710, 1720, 1730, 1740, 1750, and 1760, t ₀ Represents the time for the pressure in the system to reach steady state, and in graphical representations 1750 and 1760, t ₂ Representing the time at which the pressure increase initiates the second set of intermittent pulses. In graphical representations 1700, 1740, no adjustment is made to motor speed, and intermittent pulses of saline have been introduced as shown in graphical representations 1710, 1720, and 1730. Further, as shown in graphical representations 1750 and 1760, intermittent pulses of physiological saline have been introduced for a period of time, and a second set of intermittent pulses have been introduced for a second, later period of time.

In accordance with the disclosed concepts, a computer program product may also be provided that includes a non-transitory computer readable medium having one or more instructions that, when executed by the processor 1203, cause the processor 1203 to actuate the second drive member 1205 to pressurize and inject contrast 1214 through the fluid conduit 1201 and, when actuating the second drive member 1205, actuate the first drive member 1204 to introduce intermittent pulses of saline 1210 to create a flow wavefront interface 1211 between the saline 1210 in the fluid conduit 1201 and the contrast 1214, thereby preventing backflow of the second fluid 1214 through the fluid conduit 1201 into the first fluid reservoir 1210. According to other embodiments, the present disclosure may include a computer program product that may cause a controller to perform the various processor-initiated steps described herein.

While examples of fluid injector systems, methods of preventing backflow thereof, and computer program products are provided in the foregoing description, modifications and alterations to these examples may be made by those skilled in the art without departing from the scope and spirit of the disclosure. Accordingly, the foregoing description is intended to be illustrative rather than limiting. The disclosure described above is defined by the appended claims, and all changes to the disclosure that fall within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

1. A fluid injector system configured to perform an injection protocol, the fluid injector system comprising:

a control device operatively associated with each of two or more drive components configured to pressurize and inject a first fluid from a first fluid reservoir through a fluid conduit and at least a second fluid from a second fluid reservoir through the fluid conduit, the fluid conduit being in selective fluid communication with the first fluid reservoir and at least the second fluid reservoir, the control device comprising at least one processor programmed or configured to:

Actuating a second drive member of the two or more drive members to pressurize and inject the second fluid through the fluid conduit; and is also provided with

Upon actuation of the second drive member, a first drive member of the two or more drive members is actuated to introduce an increased flow rate or intermittent pulse of the first fluid to create turbulence in a fluid path at a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

2. The fluid injector system of claim 1, wherein the at least one processor is further programmed or configured to actuate a first drive component of the two or more drive components to continue introducing intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

3. The fluid injector system of claim 1 or 2, wherein the at least one processor is further programmed or configured to further actuate a first drive component of the two or more drive components to introduce intermittent pulses of the first fluid at a frequency or amplitude selected from the group consisting of increased frequency, decreased frequency, increased amplitude, decreased amplitude, and any combination thereof based on a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, an observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, a detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof.

4. The fluid injector system of claim 1 or 2, wherein the at least one processor is further programmed or configured to reduce at least one of a frequency and an amplitude of intermittent pulses of the first fluid or to change a waveform of intermittent pulses of the first fluid, and to deliver the first fluid at a first fluid flow rate and the second fluid at a second fluid flow rate through the fluid conduit at a desired ratio of the first fluid and the second fluid.

5. The fluid injector system of claim 1 or 2, wherein the at least one processor is further programmed or configured to monitor at least one of a pressure in the first fluid reservoir and a pressure in the second fluid reservoir during injection of the first fluid and the second fluid to determine whether a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches a first predetermined value.

6. The fluid injector system of claim 5, wherein upon reaching the first predetermined value, the at least one processor is further programmed or configured to initiate a second set of intermittent pulses of the first fluid through the fluid conduit to prevent the second fluid from entering the first fluid reservoir.

7. The fluid injector system of claim 1 or 2, wherein the at least one processor is further programmed or configured to monitor an injection pressure in the fluid conduit and determine whether the injection pressure has changed by a second predetermined value.

8. The fluid injector system of claim 1 or 2, wherein the at least one processor is further programmed or configured to calculate a predetermined injection pressure based on at least one of a programmed injection schedule and user input information, and in response, adjust a preset waveform of the intermittent pulses.

9. The fluid injector system of claim 1 or 2, wherein the at least one processor is further programmed or configured to continuously monitor a rate of change of injection pressure in the fluid conduit, and in response, adjust at least one of a pulse interval, a pulse flow rate, and a pulse quantity of the intermittent pulses based on a lookup table or a predetermined algorithm.

10. The fluid injector system of claim 1 or 2, wherein when introducing intermittent pulses of the first fluid, the at least one processor is further programmed or configured to select at least one of pulse interval, pulse flow rate, and pulse volume from a look-up table or a predetermined algorithm.

11. The fluid injector system of claim 10, wherein the at least one processor is further programmed or configured to select a pulse flow rate from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

12. The fluid injector system of claim 1 or 2, wherein the at least one processor is further programmed or configured to select an amount of pulses from a look-up table or a predetermined algorithm when intermittent pulses of the first fluid are introduced.

13. The fluid injector system of claim 10, wherein at least one of the look-up table and the predetermined algorithm is stored in a memory device.

14. The fluid injector system of claim 1 or 2, wherein less than 40 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

15. The fluid injector system of claim 14, wherein less than 25 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

16. The fluid injector system of claim 1 or 2, wherein a total volume of the first fluid introduced into the fluid conduit is less than a sum of a user-programmed volume and 15 milliliters as the first drive component introduces intermittent pulses of the first fluid to create the flow front interface between the first fluid and the second fluid in the fluid conduit.

17. The fluid injector system of claim 1 or 2, wherein upon actuation of the first drive component, the volumetric volume of the first fluid reservoir increases and no second fluid enters the first fluid reservoir.

18. A fluid injector system configured to perform an injection protocol, the fluid injector system comprising:

a control device operatively associated with each of two or more drive components, the two or more drive components configured to pressurize and inject a first fluid from a first fluid reservoir through a fluid conduit and at least a second fluid from a second fluid reservoir through the fluid conduit, the fluid conduit in selective fluid communication with the first fluid reservoir and at least the second fluid reservoir, the control device comprising at least one processor programmed or configured to:

Actuating a second drive member of the two or more drive members to pressurize and inject the second fluid through the fluid conduit;

upon actuation of the second drive member, actuating a first drive member of the two or more drive members to introduce an increased flow rate or intermittent pulse of the first fluid to create turbulence in a fluid path at a flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir;

continuing to introduce intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid;

reducing at least one of a frequency and an amplitude of intermittent pulses of the first fluid or changing a waveform of intermittent pulses of the first fluid and delivering the first fluid at a first fluid flow rate and delivering the second fluid at a second fluid flow rate through the fluid conduit at a desired ratio of the first fluid and the second fluid;

monitoring at least one of the pressure in the first fluid reservoir and the pressure in the second fluid reservoir during injection of the first fluid and the second fluid to determine if a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches a first predetermined value, or monitoring the injection pressure in the fluid conduit and determining if the injection pressure changes by a second predetermined value; and is also provided with

A second set of intermittent pulses of the first fluid is initiated through the fluid conduit upon reaching a corresponding one of the first predetermined value and the second predetermined value to prevent the second fluid from entering the first fluid reservoir.

19. The fluid injector system of claim 18, wherein the at least one processor is further programmed or configured to further actuate a first drive component of the two or more drive components to introduce intermittent pulses of the first fluid at a frequency or amplitude selected from the group consisting of increased frequency, decreased frequency, increased amplitude, decreased amplitude, and any combination thereof based on a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, an observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, a detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof.

20. The fluid injector system of claim 18 or 19, wherein the at least one processor is further programmed or configured to calculate a predetermined injection pressure based on at least one of a programmed injection scheme and user input information, and in response, adjust a preset waveform of the intermittent pulses.

21. The fluid injector system of claim 18 or 19, wherein the at least one processor is further programmed or configured to continuously monitor a rate of change of injection pressure in the fluid conduit, and in response, adjust at least one of a pulse interval, a pulse flow rate, and a pulse amount of the intermittent pulses based on a lookup table or a predetermined algorithm.

22. The fluid injector system of claim 18 or 19, wherein the at least one processor is further programmed or configured to select at least one of pulse interval, pulse flow rate, and pulse volume from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

23. The fluid injector system of claim 22, wherein the at least one processor is further programmed or configured to select a pulse flow rate from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

24. The fluid injector system of claim 18 or 19, wherein the at least one processor is further programmed or configured to select an amount of pulses from a look-up table or a predetermined algorithm when intermittent pulses of the first fluid are introduced.

25. The fluid injector system of claim 22, wherein at least one of the look-up table and the predetermined algorithm is stored in a memory device.

26. The fluid injector system of claim 18 or 19, wherein less than 40 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

27. The fluid injector system of claim 26, wherein less than 25 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

28. The fluid injector system of claim 18 or 19, wherein a total volume of the first fluid introduced into the fluid conduit is less than a sum of a user-programmed volume and 15 milliliters as the first drive component introduces intermittent pulses of the first fluid to create the flow front interface between the first fluid and the second fluid in the fluid conduit.

29. The fluid injector system of claim 18 or 19, wherein upon actuation of the first drive component, a capacitive volume of the first fluid reservoir increases and no second fluid enters the first fluid reservoir.

30. A method of preventing backflow of a second fluid from a second fluid reservoir into a first fluid reservoir in a fluid injector system configured to perform an injection protocol, the method comprising:

providing a control device operably associated with a first drive component configured to pressurize and inject the first fluid through a fluid conduit and a second drive component configured to pressurize and inject at least a second fluid from the second fluid reservoir through the fluid conduit;

actuating the second drive member to pressurize and inject the second fluid through the fluid conduit; and

31. The method of claim 30, further comprising actuating a first drive component of the two or more drive components to continue introducing intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

32. The method of claim 30 or 31, further comprising actuating a first drive component of the two or more drive components to introduce intermittent pulses of the first fluid at a frequency or amplitude selected from the group consisting of increased frequency, decreased frequency, increased amplitude, decreased amplitude, and any combination thereof based on at least one of a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, an observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof.

33. The method of claim 30 or 31, further comprising reducing at least one of a frequency and an amplitude of intermittent pulses of the first fluid or changing a waveform of intermittent pulses of the first fluid, and delivering the first fluid at a first fluid flow rate and the second fluid at a second fluid flow rate through the fluid conduit at a desired ratio of the first fluid and the second fluid.

34. The method of claim 30 or 31, further comprising monitoring at least one of a pressure in the first fluid reservoir and a pressure in the second fluid reservoir during injection of the first fluid and the second fluid to determine if a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches a first predetermined value.

35. The method of claim 34, further comprising, upon reaching the first predetermined value, initiating, with the at least one processor, a second set of intermittent pulses of the first fluid through the fluid conduit to prevent the second fluid from entering the first fluid reservoir.

36. The method of claim 30 or 31, further comprising monitoring an injection pressure in the fluid conduit and determining whether the injection pressure has changed by a second predetermined value.

37. The method of claim 30 or 31, further comprising calculating a predetermined injection pressure based on at least one of a programmed injection schedule and user input information, and in response, adjusting a preset waveform of the intermittent pulses.

38. The method of claim 30 or 31, further comprising continuously monitoring a rate of change of injection pressure in the fluid conduit, and in response, adjusting at least one of a pulse interval, a pulse flow rate, and a pulse quantity of the intermittent pulses based on a lookup table or a predetermined algorithm.

39. The method of claim 30 or 31, further comprising, when introducing intermittent pulses of the first fluid, selecting, with the at least one processor, at least one of pulse interval, pulse flow rate, and pulse volume from a look-up table or a predetermined algorithm.

40. The method of claim 39, further comprising selecting, with the at least one processor, a pulse flow rate from a look-up table or a predetermined algorithm when intermittent pulses of the first fluid are introduced.

41. The method of claim 30 or 31, further comprising selecting, with the at least one processor, an amount of pulses from a look-up table or a predetermined algorithm when introducing intermittent pulses of the first fluid.

42. The method of claim 39, wherein at least one of the look-up table and the predetermined algorithm is stored in a memory device.

43. The method of claim 30 or 31, wherein less than 40 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

44. The method of claim 43, wherein less than 25 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

45. The method of claim 30 or 31, wherein a total volume of the first fluid introduced into the fluid conduit is less than a sum of a user-programmed volume and 15 milliliters when the first drive component introduces intermittent pulses of the first fluid to create the flow front interface between the first fluid and the second fluid in the fluid conduit.

46. The method of claim 30 or 31, wherein upon actuation of the first drive component, the capacitive volume of the first fluid reservoir increases and no second fluid enters the first fluid reservoir.

47. A non-transitory computer readable medium storing a computer program product for preventing backflow of at least a second fluid from a second fluid reservoir into a first fluid reservoir using a fluid injector system configured to perform an injection protocol, the fluid injector system comprising a control device operatively associated with each of a first drive component configured to pressurize and inject a first fluid through a fluid conduit and at least a second drive component configured to pressurize and inject the second fluid through the fluid conduit, the fluid conduit in selective fluid communication with the first fluid reservoir and the second fluid reservoir, wherein the computer program product comprises a non-transitory computer readable medium comprising one or more instructions that, when executed by at least one processor, cause the at least one processor to:

Actuating the second drive member to pressurize and inject the second fluid through the fluid conduit; and is also provided with

Upon actuation of the second drive member, the first drive member is actuated to introduce intermittent pulses of increased flow rate or fluid volume of the first fluid to create turbulence in the fluid path at the flow front interface between the first fluid and the second fluid in the fluid conduit, thereby preventing backflow of the second fluid through the fluid conduit into the first fluid reservoir.

48. The non-transitory computer readable medium of claim 47, wherein the at least one processor is further caused to actuate the first drive component to continue introducing intermittent pulses of the first fluid until the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

49. The non-transitory computer readable medium of claim 47 or 48, wherein the at least one processor is further caused to actuate the first drive component to introduce intermittent pulses of the first fluid at a frequency or amplitude selected from the group consisting of increased frequency, decreased frequency, increased amplitude, decreased amplitude, and any combination thereof based on at least one of a difference in pressure in the first fluid reservoir compared to the second fluid reservoir, an observed ratio of the first fluid and the second fluid compared to a desired ratio of the first fluid and the second fluid, a change in fluid flow rate or pressure in the fluid conduit, detection of backflow of the second fluid, a difference in fluid properties of the first fluid and the second fluid, and any combination thereof.

50. The non-transitory computer readable medium of claim 47 or 48, wherein the at least one processor is further caused to decrease at least one of a frequency and an amplitude of intermittent pulses of the first fluid or to change a waveform of intermittent pulses of the first fluid and to deliver the first fluid at a first fluid flow rate and the second fluid at a second fluid flow rate through the fluid conduit at a desired ratio of the first fluid and the second fluid.

51. The non-transitory computer readable medium of claim 47 or 48, wherein the at least one processor is further caused to monitor at least one of a pressure in the first fluid reservoir and a pressure in the second fluid reservoir during injection of the first fluid and the second fluid to determine whether a difference between the pressure in the first fluid reservoir and the pressure in the second fluid reservoir reaches a first predetermined value.

52. The non-transitory computer-readable medium of claim 51, wherein upon reaching the first predetermined value, the at least one processor is further caused to initiate a second set of intermittent pulses of the first fluid through the fluid conduit to prevent the second fluid from entering the first fluid reservoir.

53. The non-transitory computer readable medium of claim 47 or 48, wherein the at least one processor is further caused to monitor an injection pressure in the fluid conduit and determine whether the injection pressure has changed by a second predetermined value.

54. The non-transitory computer readable medium of claim 47 or 48, wherein the at least one processor is further programmed or configured to calculate a predetermined injection pressure based on at least one of a programmed injection scheme and user input information, and in response, adjust a preset waveform of the intermittent pulses.

55. The non-transitory computer readable medium of claim 47 or 48, wherein the at least one processor is further caused to continuously monitor a rate of change of injection pressure in the fluid conduit and, in response, adjust at least one of a pulse interval, a pulse flow rate, and a pulse quantity of the intermittent pulses based on a lookup table or a predetermined algorithm.

56. The non-transitory computer readable medium of claim 47 or 48, wherein the intermittent pulses of the first fluid, when introduced, further cause the at least one processor to select at least one of a pulse interval, a pulse flow rate, and a pulse volume from a lookup table or a predetermined algorithm.

57. The non-transitory computer readable medium of claim 56, wherein when intermittent pulses of the first fluid are introduced, the at least one processor is further caused to select a pulse flow rate from a look-up table or a predetermined algorithm.

58. The non-transitory computer readable medium of claim 47 or 48 wherein when intermittent pulses of the first fluid are introduced, the at least one processor is further caused to select an amount of pulses from a look-up table or a predetermined algorithm.

59. The non-transitory computer readable medium of claim 56, wherein at least one of the look-up table and the predetermined algorithm is stored in a memory device.

60. The non-transitory computer readable medium of claim 47 or 48, wherein less than 40 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

61. The non-transitory computer readable medium of claim 60, wherein less than 25 milliliters of the first fluid is introduced into the fluid conduit before the pressure of the first fluid reaches substantially the same pressure as the pressure of the second fluid.

62. The non-transitory computer readable medium of claim 47 or 48 wherein, when the first drive component introduces intermittent pulses of the first fluid to create the flow wavefront interface between the first fluid and the second fluid in the fluid conduit, a total volume of the first fluid introduced into the fluid conduit is less than a sum of a user-programmed volume and 15 milliliters.

63. The non-transitory computer readable medium of claim 47 or 48, wherein upon actuation of the first drive component, the capacitive volume of the first fluid reservoir increases and no second fluid enters the first fluid reservoir.